In European Patent No. 0466726, there is set forth a cage structure useful in connection with the creation of building blocks, which can be used for sea defences, shoring hillsides, and for providing military defence walls. These structures are made of open mesh panels, for example of welded mesh material, or twisted wire construction. The advantage of the structure set forth is that the panels are used to form the walls of the structure, with the panels being pivotally connected under factory conditions and the structure can be folded to a flat collapsed condition for transportation to site. On site, simply by manipulation, the structure is capable of being moved from the collapsed condition to an erected condition, in which the structure defines a row of open topped cavities which can be filled with soil, sand, rubble or the like to form a wall (or part thereof, shoring block or the like. The invention has been successful commercially on a worldwide basis.
The type of gabion described in EP-B-0466726 has applications in the military field, as well as in civil and environmental defence. Other types of gabion have applications in landscape design and in decorative or aesthetic connections, such as garden ornaments or window boxes. It may be desirable in some circumstances to provide such gabions with a surface effect which allows the gabion fill material to be obscured from view by a surface effect material in use of the gabion.
As well as aesthetic reasons for providing a surface effect, a problem which has been encountered with some gabions is that in certain climates, particularly hot climates, the material which is used to fill the cavities formed by the panels can be susceptible to changing conditions under temperature extremes. For example the material may be caused to contract in cold weather or expand in hot weather which can cause the structure to be less rigid or threaten to “burst” the joins between the panels.
A further problem is that in certain instances it can be desirable to provide a building structure with a particular surface effect, which it might not otherwise have from the material used to fill the cavities.
It should be clear that the invention can be applied to other building structures and situations. This should be borne in mind despite the fact that in the following a structure of the type described in the applicant's patent EP0466726 is given as a particular embodiment of the invention. Other types of gabion are particularly susceptible to improvement with this invention.
In a collapsible/erectable structure it is difficult to give the walls, or one wall a different surface effect than would be achieved as a result of the materials used for the structure and the filling material. It is disclosed in the said patent that when the structure is erected and filled, the walls can be given a different surface effect by the spraying of decorative synthetic resin onto the walls of the erected structure. However, it may be desirable that the walls were to have a different surface effect, say of aesthetically attractive materials such as pebbles, turf or of other vegetation effect, or a surface effect for protective purposes that could not be achieved with the structure specifically described in the said patent.